Easy/best way to rewire bathroom light

wife/daughter's bathroom. The current wall mounted vanity lights need to g o up higher. My understanding is it is not proper to put a junction box enc losed inside a wall. Is there an easier way to move this light without havi ng to re wire from the switch to the light? The other thing is I think this light is in series with another circuit somewhere in another bathroom so w hatever I do will affect other lights.<

nothing wrong with putting a junction box in the wall. just make sure all t he connections are properly insulated from each other and the wall, that th e connections are well made, and that the wall is made good afterwards. The last requirement is only cosmetic. An easier way? errr.. magic maybe...

I appreciate it!

I agree with the you and disagree with the the other poster about putting a JB inside a wall. I guess it may be a matter of jurisdiction. In the locations that I know of, a JB must remain accessible and drywalling over a box is not considered accessible.

How many wires enter the box for the existing vanity light? And what direction do they enter from (it sounds like it/they enter from the bottom or possibly side, based on your description, but I don't want to assume)? And, which of those pairs, if any, stay live when the light switch is off? Also, how mainy wires enter the light switch box, and from what direction, and which if any stay live when the switch is off?

Don't do anything unsafe to check this out ... but if you are redoing the wiring yourself I imagine you are ok to do this. If we know where the wiring is we may be able to figure out a way to get you what you are after, and not effect other loads on the circuit (which would not be "in series" with the light, but just "on the same circuit" as the light ... I assume the light switch in the bathroom controls only one thing, the light fixture in question).

Alternatively, is there an attic above this room (or a basement with open ceilings below this room), are the tops (bottoms) of teh walls accessible, and how do you feel about fishing a wire down to (from) the light switch and new fixture?

In the UK, if connections will become inaccessible, they must be made by crimps, brazing, or soldering, i.e. long-life permanent maintenance- free methods which are not compromised by any expectation of being able to dissassemble/reassemble in the future, as they will be inaccessible.

Furthermore, the hidden cable location (and hence the hidden connection) must be in an expected location, such as in a horizontal or vertical line from a visible wiring accessory, or within a few inches of a corner or the top of the wall, or it must be > 2" deep in the wall, or protected by a steel plate in the wall.

wife/daughter's bathroom. The current wall mounted vanity lights need to g o up higher. My understanding is it is not proper to put a junction box enc losed inside a wall. Is there an easier way to move this light without havi ng to re wire from the switch to the light? The other thing is I think this light is in series with another circuit somewhere in another bathroom so w hatever I do will affect other lights.

There are two 12/2 cables coming in from the sides. I might have access to the wall under the crawl space by drilling a hole. From the top would be a little harder.

I don't have a go-to solution for you here. Right now you have wiring coming from the left into the existing electrical box, Box A, and wiring coming form the right into Box A. If you install a new Box B, say a foot above (high enough to be above the mirror) and a foot to the left of Box A, maybe you can reroute the left wiring to Box B. Similarly, if you install a Box C a foot above Box A and a foot to the right of Box A, the right hand wiring can be rerouted to Box C. Then you install a new Box D, between B and C, that the new light fixture will mount to. You have to get the left hand wiring from B to D, and the right hand wiring from C to D. Maybe that means opening some drywall, which might not be a problem if you are using a 'bath bar' type light fixture that is 24" wide or 36" or so and will cover the opened drywall. Or you could drop wires from B and C all the way to the crawlspace and back up to D (doesn't sound pleasant). Or you could do surface mount wiring (e.g. Wiremold) from Box B to D and from Box C to D.

electrical.theiet.org/wiring-matters/42/junction-boxes.cfm?type=pdf